What is glucose? What does the fall and rise of glucose mean?

By | 4 June 2021

Carbohydrates, fats, and proteins are the three major food groups that form the basis of our diet. Glucose is the building block of carbohydrates. This word means sweet in Greek and is the main energy source of our body. It is found in fruits, especially grapes, and is known as “grape sugar” among people. For our physiological activities to continue healthily, we need to consume enough carbohydrates.

Floury foods, potatoes, rice, nuts, fruits contain high levels of carbohydrates. Foods containing carbohydrates are broken down as a result of various enzymatic activities as they pass through the digestive tract and are converted into glucose, which is the building block. Glucose is absorbed from the intestines and mixes with the blood. For this reason, it is also called “blood sugar”. Glucose carried by the blood is used as an energy source in all tissues and organs. If there is more glucose in the environment than necessary, it is converted into more complex carbohydrates to be used in case of need and stored in the liver and muscles.

In healthy people, the amount of glucose in the blood is kept within certain limits thanks to the hormones insulin and glucagon secreted by the pancreas. Glucose, which is taken with food and mixed with the blood, causes blood sugar to rise, insulin organizes the passage of glucose in the blood to the cells where it will be used. Thanks to insulin, glucose in the blood is drawn into the cells and excessive accumulation of glucose in the blood is prevented. In cases of hunger, blood sugar drops. Glucagon hormone is secreted to keep blood sugar within normal limits. In this way, carbohydrates are converted into glucose, released from where they are stored, and mixed into the blood. Insulin and glucagon hormones regulate the glucose level by preventing excessive rise or fall of the glucose level in the blood.

A normal level of blood glucose within certain limits is called “normoglycemia”, lower than normal is called “hypoglycemia” and higher than normal is called “hyperglycemia”. The limits within which the blood glucose level should be determined are based on the diagnosis and treatment criteria of organizations such as the International Diabetes Federation (IDF), the American Diabetes Association (ADA).

According to international diagnostic criteria, fasting blood glucose value is expected to be below 70-100 mg/dl and postprandial blood glucose value below 140 mg/dl in healthy individuals. The value meant by fasting is the glucose value measured in the blood after 8 hours of fasting, and the meaning of satiety is measured 2 hours after food consumption.

How is glucose measured?

The blood glucose value is mainly measured by a test using the plasma portion of the blood. In hospital conditions, a certain amount of blood is taken from the patient and sent to the laboratory, the glucose value in the plasma part of the blood is calculated in the laboratory and compared with internationally accepted criteria, and interpreted by your physician. Today, it has become easier to monitor blood glucose values ​​outside of hospital conditions. Some devices measure its level instantly with a drop of blood taken from the finger at home. In this way, you can easily monitor your fasting and postprandial glucose levels at home. When you go to the hospital for your routine check-ups, you can take your glucose meter with you and make your own measurement at the same time and test the reliability of your device by comparing it with your laboratory results.

Although fasting and postprandial glucose levels can be monitored instantly at home, your doctor can evaluate your average blood glucose level in the last 2-3 months, that is, how effective your blood glucose control is in the long term, by looking at a parameter called “HbA1c (glycosylated hemoglobin)” in the hospital. This test can be done at any time and does not require prior fasting.

According to the National Diabetes Federation criteria, the HbA1c assessment is as follows:

  • Normal: Below 5.7%
  • Prediabetes (hidden sugar): 5.7% to 6.4%
  • Diabetes (diabetic): 6.5% or higher

The normal value for HbA1c varies according to the age, health status of the person, and whether or not they have diabetes. For this reason, your test results should always be evaluated by a specialist physician. It is important to have HbA1c done at the intervals recommended by your doctor according to your health status.

What is hypoglycemia?

A blood glucose level below normal. As we mentioned above, since insulin and glucagon hormones keep blood glucose at certain values, fasting blood glucose usually does not fall below 75 mg/dl in healthy individuals.

What are the causes of hypoglycemia?

Hypoglycemia may occur due to many reasons such as long-term fasting, skipping meals, various drugs, excessive physical activity, extreme fatigue, heart, liver, and kidney failures, alcohol poisoning, pancreatic tumors that cause excessive insulin production. However, it has been reported that 80% of hypoglycemia cases admitted to emergency services are caused by diabetes. Misuse of diabetes medications, especially insulin, can cause hypoglycemia.

What are the symptoms of hypoglycemia?

  • the feeling of hunger, tiredness
  • sweating, trembling
  • dizziness
  • Don’t be anxious, palpitations
  • Defect of vision
  • Pallor

When hypoglycemia is severe, unconsciousness, brain damage, and coma may occur. Recurrent hypoglycemia is dangerous and its causes must be determined by seeking medical help.

What is hyperglycemia?

Hyperglycemia is higher than normal blood glucose. Hyperglycemia is mentioned when fasting blood glucose exceeds 100 mg/dl and postprandial blood glucose exceeds 140 mg/dl. It is frequently observed in diabetic patients who receive inadequate treatment or do not receive treatment. Postprandial blood glucose above 200 mg/dl indicates diabetes. Excessive elevation of blood glucose in a short time can lead to unconsciousness, coma, and subsequent death. For this reason, regular monitoring of blood glucose is important, especially in diabetic patients. Under normal conditions, there is no glucose in the urine, when the blood glucose rises excessively and exceeds the threshold value of 180 mg/dl, it begins to be excreted in the urine. This situation is known as glycosuria, the removal of it from the blood through urine also causes water loss in the patient and worsens the picture.

What are the causes of hyperglycemia?

The most important cause is diabetes. In patients with diabetes who do not receive adequate treatment, the blood glucose remains constantly high. Apart from diabetes, exposure to excessive stress, use of steroid group drugs, various endocrinological (hormonal) diseases, kidney diseases, pancreatic cancers can also cause hyperglycemia.

What are the symptoms of hyperglycemia?

  • Frequent urination during the day and especially at night
  • Excessive thirst, drinking too much water
  • don’t get hungry often
  • dry mouth
  • Acetone-like odor in the mouth
  • Weakness, fatigue, drowsiness
  • Delayed healing of opened wounds
  • Unexplained weight loss
  • burning sensation in feet
  • Dry skin
  • blurred vision
  • recurrent infections

Diabetes is a chronic, life-long disease that occurs with insufficient production or ineffectiveness of the insulin hormone and progresses with hyperglycemia. Two types have been defined, Type I and Type II. In type I diabetes, the body perceives the beta cells, which are the insulin-producing cells of the pancreas, as foreign tissue and destroys the beta cells. For this reason, insulin cannot be produced in the body and blood sugar rises uncontrollably. In its treatment, the use of insulin is absolutely necessary.

In type II diabetes, insulin production is insufficient and insulin resistance is often seen. For this reason, insulin use may not be necessary unless the disease reaches advanced stages. 90-95% of diabetes patients all over the world have Type II diabetes. The number of patients with Type II diabetes is increasing rapidly in our country. According to the data of the International Diabetes Federation, Turkey is the country with the highest prevalence of diabetes. According to the results of the research, the prevalence of diabetes in the age range of 20-79 in Turkey is 14.85%.

Hyperglycemia is one of the most prominent symptoms of diabetes, it indicates inadequate treatment or misuse of drugs. High blood glucose levels damage your large and small vessels and nerves over time, leading to cardiovascular diseases, stroke, loss of lower limbs, kidney damage, vision loss, and blindness.

In our country, the number of patients with diabetes has increased by nearly 100% in 10 years, and approximately 60,000 people die every year due to diabetes complications such as heart attack and stroke. To prevent diabetes and diabetes-related complications, monitor your blood glucose level regularly.



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